Not only was she a Firestorm villain but in her first appearance her powers were only in her suit, a problem that made it easy for Firestorm to disarm her.

He transmuted her suit..... rendering her stark naked.

If you guessed Killer Frost, like I did, you guess too early. The "married to a super-hero" definitely makes it Plastique, who is French Canadian, and I don't believe Killer Frost is married or a foreign.